Surface treating agent including perfluoro(poly)ether-group-containing silane compound

ABSTRACT

A surface-treating agent including at least one perfluoro(poly)ether group containing silane compound of the formula (1): 
                         
wherein each of symbols is as defined herein, wherein a number average molecular weight of the perfluoro(poly)ether group containing silane compound is 3000 or more and 6000 or less, and wherein 80 mol % or more of the perfluoro(poly)ether group containing silane compound contained in the surface-treating agent is a compound wherein g is 2 or more.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/JP2016/068412, filed on Jun. 21, 2016, which claims priority fromJapanese Patent Application No. 2015-127889, filed on Jun. 25, 2015, thecontents of all of which are incorporated herein by reference in theirentirety.

TECHNICAL FIELD

The present invention relates to a surface-treating agent comprising aperfluoro(poly)ether group containing silane compound. Additionally, thepresent invention relates to an article and the like to which thesurface-treating agent is applied.

BACKGROUND ART

A certain fluorine-containing silane compound is known to be able toprovide excellent water-repellency, oil-repellency, antifoulingproperty, or the like when it is used on a surface treatment of a basematerial. A layer (hereinafter, referred to as a “surface-treatinglayer”) formed from the surface-treating agent comprising afluorine-containing silane compound is applied to various base materialssuch as a glass, a plastic, a fiber and a building material as aso-called functional thin film.

As such fluorine-containing silane compound, perfluoropolyether groupcontaining silane compound which has a perfluoropolyether group in itsmolecular main chain and a hydrolyzable group bonding to a Si atom inits molecular terminal or its terminal portion is known. For example,Patent Literature 1 describes fluorine-containing silane compoundcomprising a molecular main chain having a perfluoropolyether group anda plurality of polyethylene chains having a Si atom having ahydrolyzable group in a side chain of the polyethylene chains.

PRIOR ART LITERATURE Patent Literature

Patent Literature 1: International Publication. Number 97/7155

SUMMARY OF THE INVENTION Problem to be Solved by the Invention

The surface-treating layer is requested for high durability to provide abase material with a desired function for a long time. The layer formedfrom the surface-treating agent containing the fluorine-containingsilane compound as described in Patent literature 1 has been suitablyused in an optical member such as glasses, a touch panel or the likewhich is required to have light permeability or transparency since itcan exert the above functions even in form of a thin film. Inparticular, in these uses, the friction durability is required to befurther improved.

However, a layer formed from the conventional surface-treating agentcontaining the fluorine-containing silane compound is no longernecessarily enough to meet the increasing demand to improve the frictiondurability.

An object of the present invention is to provide a novelsurface-treating agent comprising perfluoro(poly)ether group containingsilane compound which is able to form a layer having water-repellency,oil-repellency and antifouling property as well as high frictiondurability. An object of the present invention is also to provide anarticle to which the surface-treating agent or the like is applied.

Means to Solve the Problem

As a result of intensively studying, the inventors of the presentinvention have found that a surface-treating layer having more excellentfriction durability is able to be formed by making the content of theperfluoro(poly)ether group containing silane compound, wherein thenumber of repeating units of a polyethylene chain having a Si atom inits side chain is 2 or more, 80 mol % or more in the surface-treatingagent comprising the perfluoro(poly)ether group containing silanecompound comprising a main molecular chain having a perfluoropolyethergroup and a polyethylene chain having a Si atom having a hydroxyl groupa hydrolyzable group in its side chain, and the inventors reach thepresent invention.

According to the first aspect of the present invention, there isprovided a surface-treating agent comprising at least oneperfluoro(poly)ether group containing silane compound of the formula(1):

wherein:

Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms;

PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein, a, b, c and d are each independently an integer of 0 to 90, thesum of a, b, c and d is 1 or more, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, or dis not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

R² is each independently a hydrogen atom or an inert monovalent organicgroup;

X is a hydroxyl group or OR⁴;

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group;

Y is a hydrogen atom or a halogen atom;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10;

h is an integer from 0 to 3; and

n is an integer from 1 to 3,

wherein

a number average molecular weight of the perfluoro(poly)ether groupcontaining silane compound is 3000 or more and 6000 or less, and

80 mol % or more of the perfluoro(poly)ether group containing silanecompound contained in the surface-treating agent is a compound wherein gis 2 or more.

According to the second aspect of the present invention, there isprovided a pellet comprising the surface-treating agent described above.

According to the third aspect of the present invention, there isprovided an article comprising a base material and a layer which isformed on a surface of the base material from the surface-treating agentdescribed above.

According to the fourth aspect of the present invention, there isprovided a process for preparing a surface-treating agent comprising aperfluoro(poly)ether group containing silane compound of the formula (1)

wherein:

Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms;

PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0 to 90, thesum of a, b, c and d is at least 1, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

R² is each independently a hydrogen atom or an inert monovalent organicgroup;

X is a hydroxyl group or OR⁴;

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group;

Y is a hydrogen atom or a halogen atom;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10;

h is an integer from 0 to 3; and

n is an integer from 1 to 3,

wherein a number average molecular weight of the perfluoro(poly)ethergroup containing silane compound is 3000 or more and 6000 or less, and

80 mol % or more of the perfluoro(poly)ether group containing silanecompound contained in the surface-treating agent is a compound wherein gis 2 or more, comprising the steps of:

reacting a perfluoro(poly)ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined for the formula (1) andY¹ is chlorine, iodine or bromine, with a reactive double bondcontaining silane compound of the formula (1b):

wherein R¹, R², h and n are as defined for the formula (1), and X¹ is ahydroxyl group, a hydrolyzable group or a halogen atom

in a fluorine containing aromatic compound,

and then, optionally following steps (a) and/or (b):

(a) when Y and Y¹ are different, converting Y¹ to Y; and

(b) when X and X¹ are different, converting X¹ to X.

Effect of the Invention

According to the present invention, there is provided a novelsurface-treating agent comprising a perfluoro(poly)ether groupcontaining silane compound. By using such surface-treating agent, thesurface-treating layer having water-repellency, oil-repellency andantifouling property as well as excellent friction durability can beformed.

EMBODIMENTS TO CARRY OUT THE INVENTION

Hereinafter, the composition of the present invention will be described.

The surface-treating agent of the present invention can provide a basematerial with water-repellency, oil-repellency, antifouling property,waterproof property and friction durability, and can be suitably used asan antifouling-coating agent or a waterproof-coating agent, although thepresent invention is not particularly limited thereto.

The surface-treating agent of the present invention comprises at leastone perfluoro(poly)ether group containing silane compound of the formula(1).

In the above formula (1), Rf is an alkyl group having 1 to 10 carbonatoms which may be substituted by one or more fluorine atoms.

The “alkyl group having 1 to 10 carbon atoms” in the alkyl group having1 to 10 carbon atoms which may be substituted by one or more fluorineatoms is a straight or branched alkyl group having 1-10 carbon atoms,preferably a straight or branched alkyl group having 1-3 carbon atoms,more preferably a straight alkyl group having 1-3 carbon atoms.

The above-described Rf is preferably an alkyl group having 1 to 10carbon atoms which is substituted by one or more fluorine atoms, morepreferably a perfluoroalkyl group having 1 to 10 carbon atoms orCF₂H—C₁₋₉ perfluoroalkylene group, more preferably a perfluoroalkylgroup having 1 to 10 carbon atoms.

The perfluoroalkyl group having 1 to 10 carbon atoms is a straight orbranched perfluoroalkyl group having 1-10 carbon atoms, preferably astraight or branched perfluoroalkyl group having 1-3 carbon atoms, morepreferably a straight perfluoroalkyl group having 1-3 carbon atoms,specifically —CF₃, —CF₂CF₃ or —CF₂CF₂CF₃.

In the above-described formula (1), PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—, and corresponds to aperfluoro(poly)ether group. Herein, a, b, c and d are each independently0 or an integer of 1 or more and the sum of a, b, c and d is 1 or more.Preferably, a, b, c and d are each independently an integer of 0 or moreand 90 or less, for example an integer of 1 to 90, more preferably eachindependently an integer of 0 or more and 80 or less. Preferably, thesum of a, b, c and d is 5 or more, more preferably 10 or more, forexample 10 or more and 80 or less. The occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula. Among these repeating units, the—(OC₄F₈)— group may be any of —(OCF₂CF₂CF₂CF₂)—, —(OCF(CF₃)CF₂CF₂)—,—(OCF₂CF(CF₃)CF₂)—, —(OCF₂CF₂CF(CF₃))—, —(OC(CF₃)₂CF₂)—,—(OCF₂C(CF₃)₂)—, —(OCF(CF₃)CF(CF₃))—, —(OCF(C₂F₅)CF₂)— and—(OCF₂CF(C₂F₅))—, preferably —(OCF₂CF₂CF₂CF₂). The —(OC₃F₆)— group maybe any of —(OCF₂CF₂CF₂)—, —(OCF(CF₃)CF₂)— and —(OCF₂CF(CF₃))—,preferably —(OCF₂CF₂CF₂)—. The —(OC₂F₄)— group may be any of —(OCF₂CF₂)—and —(OCF(CF₃))—, preferably —(OCF₂CF₂)—.

In one embodiment, PFPE is —(OC₃F₆)_(b)— wherein b is an integer of 1 ormore and 40 or less, preferably 5 or more and 40 or less, morepreferably 10 or more and 40 or less, preferably —(OCF₂CF₂CF₂)_(b)—wherein b is an integer of 1 or more and 40 or less, preferably 5 ormore and 40 or less, more preferably 10 or more and 40 or less.

In another embodiment, PFPE is—(OC₄F₈)—(OC₃F₈)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a and b are eachindependently an integer of 0 or more and 30 or less, and c and d areeach independently an integer of 1 or more and 90 or less, preferably 5or more and 90 or less, more preferably 10 or more and 90 or less. Theoccurrence order of the respective repeating units in parentheses withthe subscript a, b, c or d is not limited in the formula. Preferably,PFPE is —(OCF₂CF₂CF₂CF₂)_(a)—(OCF₂CF₂CF₂)_(b)—(OCF₂CF₂)_(c)—(OCF₂)_(d)—.

In further another embodiment, PFPE is a group of —(OC₂F₄—R¹¹)_(n)—. Inthe formula, R¹¹ is a group selected from OC₂F₄, OC₃F₆ and OC₄F₈, or acombination of 2 or 3 groups independently selected from these groups.The combination of 2 or 3 groups independently selected from OC₂F₄,OC₃F₆ and OC₄F₆ includes, but are not particularly limited to, forexample —OC₂F₄OC₃F₆—, —OC₂F₄OC₄F₈—, —OC₃F₆OC₂F₄—, —OC₃F₆OC₃F₆—,—OC₃F₆OC₄F₈—, —OC₄F₈OC₄F₈—, —OC₄F₈OC₃F₆—, —OC₄F₈OC₂F₄—,—OC₂F₄OC₂F₄OC₃F₆—, —OC₂F₄OC₂F₄OC₄F₈—, —OC₂F₄OC₃F₆OC₂F₄—,—OC₂F₄OC₃F₆OC₃F₆—, —OC₂F₄OC₄F₈OC₂F₄—, —OC₃F₆OC₂F₄OC₂F₄—,—OC₃F₆OC₂F₄OC₃F₆—, —OC₃F₆OC₃F₆OC₂F₄—, —OC₄F₈OC₂F₄OC₂F₄—, and the like.The above-described n″ is an integer of 2 to 90, preferably an integerof 2 to 50. In the formula, OC₂F₄, OC₃F₆ and OC₄F₆ may be straight orbranched, preferably straight. In this embodiment, PFPE is preferably—(OC₂F₄—OC₃F₆)_(n″)— or —(OC₂F₄—OC₄F₈)_(n″)—.

In the above-described formula (1), Q is an oxygen atom or a divalentorganic group.

The above-described “divalent organic group” as used herein represents adivalent group containing a carbon. Examples of the divalent organicgroup include, but are not particularly limited to, a divalent groupobtained by removing further one hydrogen atom from a hydrocarbon group.

The above-described “hydrocarbon group” as used herein represents agroup containing a carbon atom and a hydrogen atom. Examples of thehydrocarbon group include, but are not particularly limited to, ahydrocarbon group having 1-20 carbon atoms which may be substituted byone or more substituents, for example, an aliphatic hydrocarbon group,an aromatic hydrocarbon group, and the like. The “aliphatic hydrocarbongroup” may be straight, branched or cyclic, and may be saturated orunsaturated. The hydrocarbon group may contain one or more ringstructures. It is noted that the hydrocarbon group may have one or moreN, O, S, Si, amide, sulfonyl, siloxane, carbonyl, carbonyloxy, or thelike at its terminal or in its molecular chain.

Examples of the substituent of the above-described “hydrocarbon group”include, but are not particularly limited to, for example a halogen atomsuch as a fluorine atom, a chlorine atom, a bromine atom or an iodineatom, preferably a fluorine atom; and a C₁₋₆ alkyl group, a C₂₋₆ alkenylgroup, a C₂₋₆ alkynyl group, a C₃₋₁₀ cycloalkyl group, a C₃₋₁₀unsaturated cycloalkyl group, a 5-10 membered heterocyclyl group, a 5-10membered unsaturated heterocyclyl group, a C₆₋₁₀ aryl group, a 5-10membered heteroaryl group, and the like which may be substituted by oneor more halogen atoms.

In one embodiment, Q may be a C₁₋₂₀ alkylene group or—(CH₂)s-Q′-(CH₂)_(t)—. In the formula, Q′ is —O—, or —(Si(R³)₂O)_(l)— or—O—(CH₂)_(m)—(Si(R³)₂)_(l)— (wherein R³ is each independently at eachoccurrence a C₁₋₆ alkyl group, l is an integer of 1 to 100, m is aninteger of 1 to 20), preferably —O—. s is an integer of 1 to 20,preferably an integer from 1 to 3, more preferably 1 or 2. t is aninteger of 1 to 20, preferably an integer of 2 to 3. These groups may besubstituted by one or more substituents selected from a fluorine atomand a C₁₋₃ alkyl group.

In another embodiment, Q may be —(R²⁰)_(m′)—O_(n′)—. In the formula, R²⁰is each independently at each occurrence a C₁₋₂₀ alkylene group whichmay be substituted by one or more fluorine atoms, preferably a C₁₋₁₀alkylene group which may be substituted by one or more fluorine atoms,more preferably a C₁, alkylene group which may be substituted by one ormore fluorine atoms. Examples of R²⁰ include, for example, —CH₂—, —CHF—,—CF₂—, —CH(CF₃)—, —CF(CF₃)—, —CH(CH₃)—, —CF(CH₃)—, and the like. In theformula, m′ is an integer of 1 to 20, preferably 1 to 10. In theformula, n′ is an integer from 1 to 10, preferably 1 to 5, preferably 1to 3. It is noted that the occurrence order of the respective repeatingunits in parentheses with the subscript m′ or n′ is not limited in theformula.

Specific examples of Q include, for example:

-   —CH₂O(CH₂)₃—,-   —CH₂O(CH₂)₆—,-   —CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂(CH₂)₂—,-   —CH₂O(CH₂)₃Si(CH₃)₂OSi(CH₃)₂OSi(CH₃)₂(CH₂)₂—,-   —CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂Si(CH₃)₂(CH₂)₂—,-   —CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₃Si(CH₃)₂(CH₂)₂—,-   —CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₁₀Si(CH₃)₂(CH₂)₂—,-   —CH₂O(CH₂)₃Si(CH₃)₂O(Si(CH₃)₂O)₂₀Si(CH₃)₂(CH₂)₂—,-   —CH₂OCF₂CHFOCF₂—,-   —CH₂OCF₂CHFOCF₂CF₂—,-   —CH₂OCF₂CHFOCF₂CF₂CF₂—,-   —CH₂OCH₂CF₂CF₂OCF₂—,-   —CH₂OCH₂CF₂CF₂OCF₂CF₂—,-   —CH₂OCH₂CF₂CF₂OCF₂CF₂CF₂—,-   —CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂—,-   —CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂—,-   —CH₂OCH₂CF₂CF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,-   —CH₂OCH₂CHFCF₂OCF₂—,-   —CH₂OCH₂CHFCF₂OCF₂CF₂—,-   —CH₂OCH₂CHFCF₂OCF₂CF₂CF₂—,-   —CH₂OCH₂CHFCF₂OCF(CF₃)CF₂OCF₂—,-   —CH₂OCH₂CHFCF₂OCF(CF₃)CF₂OCF₂CF₂—,-   —CH₂OCH₂CHFCF₂OCF(CF₃)CF₂OCF₂CF₂CF₂—,    and the like.

In the above-described formula (1), R¹ is a hydrogen atom or an alkylgroup having 1 to 22 carbon atoms. The alkyl group having 1 to 22 carbonatoms may be preferably a straight or branched alkyl group having 1 to 3carbon atoms.

In the above-described formula (1), R² is a group binding to Si, and iseach independently a hydrogen atom or an inert monovalent organic group.

The “inert monovalent organic group” is a group in which a bonding to Siis substantially not cleaved by hydrolysis. It may be, but not limitedto, for example an alkyl group having 1 to 22 carbon atoms, preferablyan alkyl group having 1 to 3 carbon atoms.

In the above-described formula (1), X is a group bonding to Si, and is ahydroxyl group or OR⁴. The hydroxyl group may be, but is notparticularly limited to, a group generated by hydrolysis of OR⁴.

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group.

X is preferably a hydroxyl group, —O(R⁴) (wherein R⁴ is a C₁₋₁₂ alkylgroup, preferably a C₁₋₆ alkyl group, more preferably a C₁₋₃ alkylgroup), more preferably, —OCH₃, —OCH₂CH₃, or —OCH(CH₃)₂. These groupsmay be substituted by one or more substituents selected from, forexample, a fluorine atom, a C₁₋₆ alkyl group, a C₂₋₆ alkenyl group, anda C₂₋₆ alkynyl group.

In the above-described formula (1), Y is a hydrogen atom or a halogenatom. The halogen atom is preferably an iodine atom, a chlorine atom, abromine atom, further preferably an iodine atom.

In the above-described formula (1), Z is a fluorine atom or afluoroalkyl group having 1 to 5 carbon atoms. The fluoroalkyl grouphaving 1 to 5 carbon atoms is, for example, a fluoroalkyl group having 1to 3 carbon atoms, preferably a perfluoroalkyl group having 1 to 3carbon atoms, more preferably a trifluoromethyl group or apentafluoroethyl group, further preferably a trifluoromethyl group.

In the above-described formula (1), e is an integer from 0 to 3. Inanother embodiment, e is an integer from 1 to 3.

In the above-described formula (1), f is 0 or 1.

In the above-described formula (1), h is an integer from 0 to 3.

In the above-described formula (1), n is an integer from 1 to 3.

In the above-described formula (1), g is an integer from 1 to 10.Preferably, g is an integer of 2 to 6.

Eighty mol % or more, preferably 90 mol % or more of theperfluoro(poly)ether group containing silane compound contained in thesurface-treating agent of the present invention is a compound wherein g(i.e., the number of the repeating units of a silane containing group)is 2 or more, preferably 2 or more and 6 or less.

In one embodiment, 60 mol % or more, preferably 70 mol % or more, morepreferably 75 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent of the presentinvention is a compound wherein g is 2 or more and 4 or less.

In a preferable embodiment, 50 mol % or more, preferably 60 mol % ormore, more preferably 70 mol % or more, further preferably 80 mol % ormore of the perfluoro(poly)ether group containing silane compoundcontained in the surface-treating agent of the present invention is acompound wherein g is 3 or more, preferably 3 or more and 6 or less.

In one embodiment, 30 mol % or more, preferably 50 mol % or more, morepreferably 65 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent of the presentinvention is a compound wherein g is 3 or more and 4 or less.

In a preferable embodiment, in the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent of the presentinvention, an average (number average) of “g” is 2.0 or more, preferably2.6 or more, more preferably 3.0 or more. The upper limit of the averageof “g” may be, but not particularly limited to, for example, 6.0 or lessor 5.0 or less.

In a further preferable embodiment, in the perfluoro(poly)ether groupcontaining silane compound contained in the surface-treating agent ofthe present invention, polydispersity of “g” is more than 1.0 and lessthan 2.0, preferably more than 1.0 and less than 1.5, more preferablymore than 1.0 and less than 1.3.

The “polydispersity of g” in the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent means aproportion of “a weight average of g” to “a number average of g” (i.e.,the weight average of g/the number average of g) in theperfluoro(poly)ether group containing silane compound contained in thesurface-treating agent.

The “number average of g” can be calculated by the following equation(a), and the “weight average of g” can be calculated by the followingequation (b):Σ(g _(i) N _(i))/ΣN _(i)  Equation (a):Σ(g _(i) ² N _(i))/Σ(g _(i) N _(i))  Equation (b):wherein, i is an integer of 1 or more, g_(i), is a value of g when thenumber of the repeating units of the silane-containing group is i, andN_(i) is the number of the compounds when the number of the repeatingunits of the silane-containing group is i.

The number of the repeating units of the silane-containing group in theperfluoro(poly)ether group containing silane compound, and the number ofthe perfluoro(poly)ether group containing silane compound for each ofthe number of the repeating units can be measured by usingMatrix-assisted laser desorption time-of-flight mass spectrometry(MALDI-TOF-MS).

When the number of the respective repeating units of theperfluoropolyether (PFPE) (a, b, c, and d) and the number of the silaneunits (g) are measured by using Matrix-assisted laser desorptiontime-of-flight mass spectrometry (MALDI-TOF-MS), after adding acationizing agent (an ionizing agent) and/or a matrix at an arbitraryratio to the compound of the formula (1), the measurement is conducted.

The mixing ratio of the cationizing agent and/or the matrix ispreferably, 0 part by mass or more and 1 part by mass or less, morepreferably 0 part by mass or more and 0.1 parts by mass or less withrespect to 100 parts by mass of the compound of the formula (1),respectively.

The cationizing agent (the ionizing agent) is not limited as long as itcan effectively ionize the compound of the formula (1), and may be aliquid or a solid. Examples of the cationizing agent include, forexample, sodium chloride, potassium chloride, sodium iodide, potassiumiodide, lithium trifluoroacetate, sodium trifluoroacetate, potassiumtrifluoroacetate and silver trifluoroacetate. More preferably, sodiumiodide, sodium trifluoroacetate, or silver trifluoroacetate is used.

The matrix is not limited as long as it achieves elimination andionization of a molecular to be analyzed which coexists with it byabsorbing a light energy of a laser, and may be a liquid or a solid.Examples of the matrix include, for example, 1,8-diaminonaphthalene(1,8-DAN), 2,5-dihydroxybenzoic acid (hereinafter, sometimes abbreviatedas “DHB”), 1,8-anthracene dicarboxylic acid dimethyl ester,leucoquinizarin, anthrarobin, 1,5-aminonaphthalene (1,5-DAN),6-aza-2-thiothymine, 1,5-aminoanthraquinone, 1,6-diaminopyrene,3,6-diaminocarbazole, 1,8-anthracene dicarboxylic acid, norharman,1-pyrene propylamine hydrochloride, 9-aminofluorene hydrochloride,ferulic acid, dithranol (DIT), 2-(4-hydroxyphenylazo)benzoic acid(HABA),trans-2-[3-(4-tert-butylphenyl)-2-methyl-2-propenylidene]malononitrile(DCTB), trans-4-phenyl-3-butene-2-one (TPBO), trans-3-indole acrylicacid (IAA), 1,10-phenanthroline, 5-nitro-1,10-phenanthroline,α-cyano-4-hydroxy cinnamic acid (CHCA), sinapinic acid (SA),2,4,6-trihydroxy acetophenone (THAP), 3-hydroxy picolinic acid (HPA),anthranilic acid, nicotinic acid, 3-aminoquinoline,2-hydroxy-5-methoxybenzoic acid, 2,5-dimethoxybenzoic acid,4,7-phenanthroline, p-coumaric acid, 1-iso-quinolinol, 2-picolinic acid,1-pyrenebutyric acid hydrazide (PBH), 1-pyrenebutyric acid (PBA),1-pyrenemethylamine hydrochloride (PMA), 3-AC (aminoquinoline)-CHCA,pentafluorobenzoic acid, and penta-fluorocinnamic acid. More preferably,IAA, DIT, DHB, CHCA, or 2-hydroxy-5-methoxybenzoic acid is used.

The perfluoro(poly)ether group containing silane compound of the formula(1) of the present invention has a number average molecular weight of3000 or more and 6000 or less. The perfluoro(poly)ether group containingsilane compound has a number average molecular weight of preferably3,000-5,500, more preferably 3,000-5,000, further preferably3,000-4,500. By setting the number average molecular weight to less than6,000, a reaction time for synthesizing the compound can be reduced, andthe solubility of the compound becomes higher, thus it becomes easier toapply the compound by a wet coating method. It is noted that the“average molecular weight” in the present invention means a numberaverage molecular weight, and the “average molecular weight” is definedas a value measured by using ¹⁹F-NMR.

Next, a process for preparing the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent of the presentinvention will be described.

The compound of the formula (1):

wherein:

Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms;

PFPE is(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0 to 90, thesum of a, b, c and d is at least 1, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

R² is each independently a hydrogen atom or an inert monovalent organicgroup;

X is a hydroxyl group or OR⁴;

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group;

Y is a hydrogen atom or a halogen atom;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10;

h is an integer from 0 to 3; and

n is an integer from 1 to 3,

comprised in the surface-treating agent of the present invention can beprepared by reacting a perfluoro(poly)ether compound of the formula(1a):

wherein Rf, PFPE, Q, Z, e and f are as defined for the formula (1) andY¹ is a chlorine, an iodine or a bromine, preferably an iodine,

with a reactive double bond containing silane compound of the formula(1b):

wherein R¹, R², h and n are as defined for the formula (1), and X¹ is ahydroxyl group, a hydrolyzable group or a halogen atom (for example, achlorine, an iodine or a bromine, preferably a chlorine), and then,optionally conducting following steps (a) and/or (b):

(a) when Y and Y¹ are different, converting Y¹ to Y; and

(b) when X and X¹ are different, converting X¹ to X. The order of thesteps (a) and (b) is not particularly limited, and both steps may besimultaneously conducted.

The reaction as described above is, for example, described in JP01-294709 A.

In the perfluoro(poly)ether group containing silane compound of theformula (1) obtained as described above, when the compound wherein g is2 or more is less than a predetermined percentage, an adjustment can beconducted by various methods so that the compound wherein g is 2 or moreis not less than the predetermined percentage. For example, g can beadjusted to 2 or more by further reacting the compound of the formula(1) wherein Y is a halogen obtained in the above step with the compoundof the formula (1b).

In a preferable embodiment, the reaction of the compound of the formula(1a) with the compound of the formula (1b) is conducted in a fluorinecontaining aromatic compound.

Examples of the fluorine containing aromatic compound include, but arenot particularly limited to, for example, perfluorobenzene,pentafluorobenzene, 1,2,3,4-tetrafluorobenzene,1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene,1,2,3-trifluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene,benzotrifluoride, fluorobenzene, 1-chloro-2-fluorobenzene,l-chloro-3-fluorobenzene, 1-chloro-4-fluorobenzene,2,6-dichlorofluorobenzene, 1-fluoro-3-(trifluoromethoxy)benzene,1-fluoro-2,4-dinitrobenzene, 2,4-dimethoxy-1-fluorobenzene,1-fluoro-4-nitrobenzene, 2-fluorotoluene, 3-fluorotoluene,4-fluorotoluene, 3-fluorobenzotrifluoride, 1-chloro-2,4-difluorobenzene,l-chloro-3,4-difluorobenzene, 1-chloro-3,5-difluorobenzene,2-chloro-1,3-difluorobenzene, chloropentafluorobenzene,2,4-dichlorofluorobenzene, 2,5-dichlorofluorobenzene,2,6-dichlorofluorobenzene, 1,2-dichloro-4-fluorobenzene,1,3-dichloro-5-fluorobenzene, 1,3-dichloro-2,4,6-trifluorobenzene,3,4-difluorobenzonitrile, 3,5-difluorobenzonitrile,3,4-difluoronitrobenzene, 1-ethoxy-2,3-difluorobenzene,1,2-dicyano-4,5-difluorobenzene, 1-acetoxy-3-fluorobenzene,1-acetoxy-4-fluorobenzene, 1-acetonyl-4-fluorobenzene,2-fluoro-m-xylene, 3-fluoro-o-xylene, 4-fluoro-o-xylene,pentafluoroanisole, tetrafluorophthalonitrile, 2-trifluoromethylbenzalchloride, 3-trifluoromethylbenzal chloride, 4-trifluoromethylbenzalchloride, methyl 3-(trifluoromethyl)benzoate, difluorobenzonitrile,bistrifluoromethyl benzonitrile, 4-trifluoromethyl benzonitrile,aminobenzotrifluoride, and trifluoromethylaniline.

Preferably fluorine containing aromatic compound is perfluorobenzene,pentafluorobenzene, 1,2,3,4-tetrafluorobenzene,1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene,1,2,3-trifluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene,benzotrifluoride, fluorobenzene, 1-chloro-2-fluorobenzene,1-chloro-3-fluorobenzene, 1-chloro-4-fluorobenzene,2,6-dichlorofluorobenzene, 1-fluoro-3-(trifluoromethoxy)benzene,1-fluoro-2,4-dinitrobenzene, 2,4-dimethoxy-1-fluorobenzene,1-fluoro-4-nitrobenzene, 2-fluorotoluene, 3-fluorotoluene,4-fluorotoluene, 3-fluorobenzotrifluoride, 1-chloro-2,4-difluorobenzene,1-chloro-3,4-difluorobenzene, 1-chloro-3,5-difluorobenzene,2-chloro-1,3-difluorobenzene, chloropentafluorobenzene,2,4-dichlorofluorobenzene, 2,5-dichlorofluorobenzene,2,6-dichlorofluorobenzene, 1,2-dichloro-4-fluorobenzene,1,3-dichloro-5-fluorobenzene, 1,3-dichloro-2,4,6-trifluorobenzene,3,4-difluorobenzonitrile, 3,5-difluorobenzonitrile,3,4-difluoronitrobenzene, 1-ethoxy-2,3-difluorobenzene,1,2-dicyano-4,5-difluorobenzene, 1-acetoxy-3-fluorobenzene,1-acetoxy-4-fluorobenzene, 1-acetonyl-4-fluorobenzene,2-fluoro-m-xylene, 3-fluoro-o-xylene, 4-fluoro-o-xylene,pentafluoroanisole, tetrafluorophthalonitrile, 2-trifluoromethylbenzalchloride, 3-trifluoromethylbenzal chloride, 4-trifluoromethylbenzalchloride, methyl 3-(trifluoromethyl)benzoate, difluorobenzonitrile,bistrifluoromethyl benzonitrile, or 4-trifluoromethyl benzonitrile.

More preferable fluorine containing aromatic compound is a fluorinecontaining aromatic compound wherein polarizability is 0 debye or moreand 3 debyes or less, in particular more than 0 debye and 3 debyes orless.

Examples of the fluorine containing aromatic compound wherein thepolarizability is 0 debye or more and 3 debyes or less include, but arenot particularly limited to, for example, benzotrifluoride,difluorobenzonitrile, and bistrifluoromethyl benzonitrile.

The fluorine containing aromatic compound is a fluorine containingaromatic compound having a boiling point of preferably 120° C. or more,more preferably 150° C. or more, further preferably 180° C. or more.Examples of the fluorine containing aromatic compound includedifluorobenzonitrile, bistrifluoromethyl benzonitrile, particularlypreferably bistrifluoromethyl benzonitrile.

In a preferable embodiment, the reaction of the compound of the formula(1a) with the compound of the formula (1b) can be generally conducted at−20 to +150° C., preferably 130 to 180° C., more preferably 140 to 180°C., under an ambient pressure or in a nitrogen stream, in the presenceof an initiator or light. As the initiator, for example, a radicalgenerating agent such as a fluorine-containing diacyl peroxide, IPP(diisopropyl peroxydicarbonate), AIBN (azobisisobutyronitrile), DTBP(di-t-butyl peroxide) is used.

In a preferable embodiment, the step (a) and the step (b) are conductedin the presence of at least one catalyst selected from zinc and tin.

In a preferable embodiment, the present invention provides a process forpreparing a perfluoro(poly)ether group containing silane compound of theformula (1′):

wherein:

-   -   Rf is an alkyl group having 1 to 10 carbon atoms which may be        substituted by one or more fluorine atoms;

PFPE is(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein, a, b, c and d are each independently an integer of 0 to 200,the sum of a, b, c and d is at least 1, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

X is a hydroxyl group or a hydrolyzable group;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10; and

h is an integer from 0 to 3;

which comprises the steps of:

reacting a perfluoro (poly) ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined above, and Y¹ is achlorine, an iodine or a bromine, with a compound of the formula (1c):

wherein R¹ and h are as defined above, in a fluorine containing aromaticcompound, preferably at −20 to +150° C. under an ambient pressure or ina nitrogen stream, in the presence of an initiator (for example, aradical generating agent such as a fluorine-containing diacyl peroxide,IPP (diisopropyl peroxydicarbonate), AIBN (azobisisobutyronitrile), DTBP(di-t-butyl peroxide)) or light to obtain a compound of the formula(1d):

wherein Rf, PFPE, Q, Y¹, Z, R¹, e, f, g and h are as defined above, andthen

reacting the obtained compound with a compound of HX wherein X is asdefined above in the presence of at least one catalyst selected fromzinc and tin.

Examples of the fluorine containing aromatic compound includes the samecompounds as the fluorine containing aromatic compounds described above.In particular, it is preferably the fluorine containing aromaticcompound wherein the polarizability is 0 debye or more and 3 debyes orless, preferably more than 0 debye and 3 debyes or less. Particularpreferably, m-xylene hexafluoride is used.

According to the above embodiment, the perfluoro(poly)ether groupcontaining silane compound containing 80 mol % or more, preferably 90mol % or more of a compound wherein g is 2 or more, and havingpolydispersity of more than 1.0 and not more than 2.0 can be obtained.

Although the present invention is not bound to any theory, it ispresumed that by conducting the reaction in the fluorine containingaromatic compound, the solubility of a vinyl silane monomer in a solventis increased and an addition reaction of the vinyl silane monomer isfacilitated, as a result, the repeating number of the ethylene chainhaving a Si atom in its side chain is increased.

Hereinbefore, the process for preparation of the perfluoro(poly)ethergroup containing silane compound comprised in the surface-treating agentof the present invention is described. However, the process forpreparation of the compound is not limited thereto, and can be preparedby using various methods.

The present invention also provides the surface-treating agentcomprising the compound prepared by using the process for preparationdescribed above.

Specifically, the present invention provides a surface-treating agentcomprising at least one perfluoro(poly)ether group containing silanecompound of the formula (1):

wherein:

Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms;

PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0 to 90, thesum of a, b, c and d is at least 1, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

R² is each independently a hydrogen atom or an inert monovalent organicgroup;

X is a hydroxyl group or OR⁴;

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group;

Y is a hydrogen atom or a halogen atom;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10;

h is an integer from 0 to 3; and

n is an integer from 1 to 3,

wherein the perfluoro(poly)ether group containing silane compound of theformula (1) is prepared by reacting a perfluoro(poly)ether compound ofthe formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined for the formula (1) andY¹ is a chlorine, an iodine or a bromine,

with a reactive double bond containing silane compound of the formula(1b):

wherein R¹, R², h and n are as defined for the formula (1), and X¹ is ahydroxyl group, a hydrolyzable group or a halogen atom,

in a fluorine containing aromatic compound, preferably at −20 to +150°C. under an ambient pressure or in a nitrogen stream, in the presence ofan initiator (for example, a radical generating agent such as afluorine-containing diacyl peroxide, IPP, AIBN, DTBP) or light, andthen, optionally conducting following steps (a) and/or (b):

(a) when Y and Y¹ are different, converting Y¹ to Y; and

-   -   (b) when X and X¹ are different, converting X¹ to X.

In a preferable embodiment, the present invention provides asurface-treating agent comprising at least one perfluoro(poly)ethergroup containing silane compound of the formula (1′):

wherein:

Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms;

PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)—

wherein a, b, c and d are each independently an integer of 0 to 90, thesum of a, b, c and d is at least 1, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula;

Q is an oxygen atom or a divalent organic group;

R¹ is a hydrogen atom or an alkyl group having 1 to 22 carbon atoms;

X is a hydroxyl group or OR⁴;

R⁴ is each independently at each occurrence a substituted orunsubstituted C₁₋₁₂ alkyl group;

Z is a fluorine atom or a fluoroalkyl group having 1 to 5 carbon atoms;

e is an integer from 0 to 3;

f is 0 or 1;

g is an integer from 1 to 10; and

h is an integer from 0 to 3;

wherein the perfluoro(poly)ether group containing silane compound of theformula (1′) is prepared by reacting a perfluoro(poly)ether compound ofthe formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined above, and Y¹ is achlorine, an iodine or a bromine, with a compound of the formula (1c):

wherein R¹ and h are as defined above, in a fluorine containing aromaticcompound, preferably at −20 to +150° C. under an ambient pressure or ina nitrogen stream, in the presence of an initiator (for example, aradical generating agent such as a fluorine-containing diacyl peroxide,IPP, AIBN, DTBP) or light to obtain a compound of the formula (1d):

wherein Rf, PFPE, Q, Y¹, Z, R¹, e, f, g and h are as defined above, andthen

reacting the obtained compound with a compound of HX wherein X is asdefined above in the presence of at least one catalyst selected fromzinc and tin.

The surface-treating agent of the present invention may comprise asolvent in addition to the compound of the formula (1).

As the solvent described above, in view of stability of thesurface-treating agent of the present invention and volatile property ofthe solvent, the following solvents are preferably used: an aliphaticperfluorohydrocarbon having 5-12 carbon atoms (for example,perfluorohexane, perfluoromethylcyclohexane andperfluoro-1,3-dimethylcyclohexane); an aromatic polyfluorohydrocarbon(for example, bis(trifluoromethyl)benzene); an aliphaticpolyfluorohydrocarbon; a hydrofluoroether (HFE) (for example, an alkylperfluoroalkyl ether such as perfluoropropyl methyl ether (C₃F₇OCH₃),perfluorobutyl methyl ether (C₄F₉OCH₃), perfluorobutyl ethyl ether(C₄F₉OC₂H₅), and perfluorohexyl methyl ether (C₂F₅CF(OCH₃)C₃F₇) (theperfluoroalkyl group and the alkyl group may be liner or branched)), orthe like. These solvents may be used alone or as a mixture of 2 or morecompounds. Among them, the hydrofluoroether is preferable,perfluorobutyl methyl ether (C₄F₉OCH₃) and/or perfluorobutyl ethyl ether(C₄F₉OC₂H₅) are particularly preferable.

The surface-treating agent of the present invention may comprise othercomponents in addition to the compound of the formula (1). Examples ofthe other components include, but are not particularly limited to, forexample, a (non-reactive) fluoropolyether compound which may be alsounderstood as a fluorine-containing oil, preferably aperfluoro(poly)ether compound (hereinafter, referred to as “thefluorine-containing oil”), a (non-reactive) silicone compound which maybe also understood as a silicone oil (hereinafter referred to as “asilicone oil”), a catalyst, and the like.

Examples of the above-described fluorine-containing oil include, but arenot particularly limited to, for example, a compound of the followinggeneral formula (2) (a perfluoro(poly)ether compound).Rf¹—(OC₄F₈)_(a′)—(OC₃F)_(b′)—(OC₂F₄)_(c′)—(OCF₂)_(d′)—Rf²  (2)

In the formula, Rf¹ is an alkyl group having 1-16 carbon atoms which maybe substituted by one or more fluorine atoms (preferably, aperfluoroalkyl group having 1-16 carbon atoms), Rf² is an alkyl grouphaving 1-16 carbon atoms which may be substituted by one or morefluorine atoms (preferably, a perfluoroalkyl group having 1-16 carbonatoms), a fluorine atom or a hydrogen atom, and more preferably, Rf¹ andRf² are each independently a perfluoroalkyl group having 1-3 carbonatoms.

Subscripts a′, b′, c′ and d′ are the repeating number of each of fourrepeating units of perfluoropolyether which constitute a main backboneof the polymer, and are each independently an integer of 0 or more and300 or less, preferably an integer of 1 or more and 100 or less, and thesum of a′, b′, c′ and d′ is at least 1, preferably 5 or more, morepreferably 10 or more. The sum of a′, b′, c′ and d′ is preferably 5 ormore, more preferably 10 or more, for example, 10 or more and 100 orless. The occurrence order of the respective repeating units inparentheses with the subscript a′, b′, c′ or d′ is not limited in theformulae. Among these repeating units, the —(OC₄F₈)— group may be any of—(OCF₂CF₂CF₂CF₂)—, —(OCF(CF₃)CF₂CF₂)—, —(OCF₂CF(CF₃)CF₂)—,—(OCF₂CF₂CF(CF₃))—, —(OC(CF₃)₂CF₂)—, —(OCF₂C(CF₃)₂)—,—(OCF(CF₃)CF(CF₃))—, —(OCF(C₂F₅)CF₂)— and —(OCF₂CF(C₂F₅))—, preferably—(OCF₂CF₂CF₂CF₂). The —(OC₃F₆)— group may be any of —(OCF₂CF₂CF₂)—,—(OCF(CF₃)CF₂)— and —(OCF₂CF(CF₃))—, preferably —(OCF₂CF₂CF₂)—. The—(OC₂F₄)— group may be any of —(OCF₂CF₂)— and —(OCF(CF₃))—, preferably—(OCF₂CF₂)—.

Examples of the perfluoropolyether compound of the above describedgeneral formula (2) include a compound of any of the following generalformulae (2a) and (2b) (may be one compound or a mixture of two or morecompounds).Rf¹—(OCF₂CF₂CF₂)_(b′)—Rf²  (2a)Rf¹—(OCF₂CF₂CF₂CF₂)^(a′)—(OCF₂CF₂CF₂)^(b′)—(OCF₂CF₂)^(c′)—(OCF₂)_(d′)—Rf²  (2b)In these formulae:

Rf¹ and Rf² are as defined above; in the formula (2a), b′ is an integerof 1 or more and 300 or less, preferably an integer of 1 or more and 100or less; and in the formula (2b), a′ and b′ are each independently aninteger of 0 or more and 30 or less, and c′ and d′ are eachindependently an integer of 1 or more and 300 or less. The occurrenceorder of the respective repeating units in parentheses with thesubscript a′, b′, c′ or d′ is not limited in the formulae.

The above-described fluorine-containing oil may have an averagemolecular weight of 1,000-30,000. By having such average molecularweight, high surface slip property can be obtained. Additionally, whenthe surface-treating layer is formed from the surface-treating agent ofthe present invention by using deposition, the fluorine-containing oilpreferably has an average molecular weight larger than an averagemolecular weight of the perfluoro(poly)ether group containing silanecompound contained in the surface-treating agent. For example, thefluorine-containing oil may have an average molecular weight of forexample 5,000 to 30,000, preferably 10,000 to 30,000.

The fluorine-containing oil may be contained in the surface-treatingagent of the present invention, for example, at 0-500 parts by mass,preferably 0-400 parts by mass, more preferably 25-400 parts by masswith respect to 100 parts by mass of the perfluoro(poly)ether groupcontaining silane compound of the present invention (as the total masswhen two or more compounds are used; hereinafter the same shall apply).

The compound of the general formula (2a) and the compound of the generalformula (2b) may be used alone or in combination. The compound of thegeneral formula (2b) is preferable than the compound of the generalformula (2a) since the compound of the general formula (2b) provideshigher surface slip property than the compound of the general formula(2a). When they are used in combination, the mass ratio of the compoundof the general formula (2a) to the compound of the general formula (2b)is preferably 1:1 to 1:30, more preferably 1:1 to 1:10. By applying suchmass ratio, a surface-treating layer having a good balance of surfaceslip property and friction durability can be obtained.

In one embodiment, the fluorine-containing oil comprises one or morecompounds of the general formula (2b). In such embodiment, the massratio of the compound of the formula (1) to the compound of the formula(2b) in the surface-treating agent is preferably 4:1 to 1:4.

From the other point of view, the fluorine-containing oil may be acompound of the general formula A′-F wherein A′ is a C₅₋₁₆perfluoroalkyl group. The compound of A′-F is preferable because thecompound has high affinity for the compound of the formula (1) whereinRf is a C₁₋₁₀ perfluoroalkyl group.

The fluorine-containing oil contributes to increasing of surface slipproperty of the surface-treating layer.

As the above-described silicone oil, for example, a liner or cyclicsilicone oil having 2,000 or less siloxane bonds may be used. The linersilicone oil may be so-called a straight silicone oil and a modifiedsilicon oil.

Examples of the straight silicone oil include dimethylsilicone oil,methylphenylsilicone oil, and methylhydrogensilicone oil. Examples ofthe modified silicone oil include that which is obtained by modifying astraight silicone oil with alkyl, aralkyl, polyether, higher fatty acidester, fluoroalkyl, amino, epoxy, carboxyl, alcohol, or the like.Examples of the cyclic silicone oil include, for example, cyclicdimethylsiloxane oil.

The silicone oil may be contained in the surface-treating agent of thepresent invention, for example, at 0-300 parts by mass, preferably50-200 parts by mass with respect to 100 parts by mass of theperfluoro(poly)ether group containing silane compound of the presentinvention (as the total mass when two or more compounds are used;hereinafter the same shall apply).

The silicone oil contributes to increasing of surface slip property ofthe surface-treating layer.

Examples of the above-described catalyst contained in thesurface-treating agent include an acid (for example, acetic acid,trifluoroacetic acid, etc.), a base (for example, ammonia,triethylamine, diethylamine, etc.), a transition metal (for example, Ti,Ni, Sn, etc.), and the like.

The catalyst contained in the surface-treating agent facilitateshydrolysis and dehydration-condensation of the perfluoro(poly)ethergroup containing silane compound of the present invention to facilitatea formation of the surface-treating layer.

Examples of the other components other than the above-describedcomponents include, for example, tetraethoxysilane,methyltrimethoxysilane, 3-aminopropyltrimethoxysilane,3-glycidoxypropyltrimethoxysilane, methyltriacetoxysilane, and the like.

The surface-treating agent of the present invention is impregnated intoa porous material, for example, a porous ceramic material, a metal fiberfor example that obtained by solidifying a steel wool into a form ofcotton to obtain a pellet. The pellet can be used, for example, invacuum deposition.

Next, the article of the present invention will be described.

The article of the present invention comprises a base material and alayer (surface-treating layer) which is formed from the PFPE containingsilane compound or the surface-treating agent of the present invention(hereinafter, referred to simply as “surface-treating agent” as arepresentative thereof) on the surface of the base material. Thisarticle can be produced, for example, as follows.

Firstly, the base material is provided. The base material usable in thepresent invention may be composed of any suitable material such as aglass, a resin (may be a natural or synthetic resin such as a commonplastic material, and may be in form of a plate, a film, or others), ametal or a metal oxide (may be a simple substance of a metal such asaluminum, copper, or iron, or a complex such as alloy or the like), aceramic, a semiconductor (silicon, germanium, or the like), a fiber (afabric, a non-woven fabric, or the like), a fur, a leather, a wood, apottery, a stone or the like.

For example, when an article to be produced is an optical member, amaterial constituting the surface of the base material may be a materialfor an optical member, for example, a glass or a transparent plastic.For example, when an article to be produced is an optical member, anylayer (or film) such as a hard coating layer or an antireflection layermay be formed on the surface (outermost layer) of the base material. Asthe antireflection layer, either a single antireflection layer or amulti antireflection layer may be used. Examples of an inorganicmaterial usable in the antireflection layer include SiO₂, SiO, ZrO₂,TiO₂, TiO, Ti₂O₃, Ti₂O₅, Al₂O₃, Ta₂O₅, CeO₂, MgO, Y₂O₃, SnO₂, MgF₂, WO₃,and the like. These inorganic materials may be used alone or incombination with two or more (for example, as a mixture). When multiantireflection layer is formed, preferably, SiO₂ and/or SiO are used inthe outermost layer. When an article to be produced is an optical glasspart for a touch panel, it may have a transparent electrode, forexample, a thin layer comprising indium tin oxide (ITO), indium zincoxide, or the like on a part of the surface of the base material(glass). Furthermore, the base material may have an insulating layer, anadhesive layer, a protecting layer, a decorated frame layer (I-CON), anatomizing layer, a hard coating layer, a polarizing film, a phasedifference film, a liquid crystal display module, and the like,depending on its specific specification.

The shape of the base material is not specifically limited. The regionof the surface of the base material on which the surface-treating layershould be formed may be at least a part of the surface of the basematerial, and may be appropriately determined depending on use, thespecific specification, and the like of the article to be produced.

The base material may be that of which at least the surface consists ofa material originally having a hydroxyl group. Examples of such materialinclude a glass, in addition, a metal on which a natural oxidized filmor a thermal oxidized film is formed (in particular, a base metal), aceramic, a semiconductor, and the like. Alternatively, as in a resin,when the hydroxyl groups are present but not sufficient, or when thehydroxyl group is originally absent, the hydroxyl group can beintroduced on the surface of the base material, or the number of thehydroxyl group can be increased by subjecting the base material to anypretreatment. Examples of the pretreatment include a plasma treatment(for example, corona discharge) or an ion beam irradiation. The plasmatreatment may be suitably used to introduce the hydroxyl group into orincrease it on the surface of the base material, further, to clarify thesurface of the base material (remove foreign materials, and the like).Alternatively, other examples of the pretreatment include a methodwherein a monolayer of a surface adsorbent having a carbon-carbonunsaturated bond group is formed on the surface of the base material byusing a LB method (Langmuir-Blodgett method) or a chemical adsorptionmethod beforehand, and then, cleaving the unsaturated bond under anatmosphere of oxygen and nitrogen.

Alternatively, the base material may be that of which at least thesurface consists of a material comprising other reactive group such as asilicon compound having one or more Si—H groups or alkoxysilane.

Next, the film of the above surface-treating agent of the presentinvention is formed on the surface of the base material, and the film ispost-treated, as necessary, and thereby the surface-treating layer isformed from the surface-treating agent.

The formation of the film of the surface-treating agent of the presentinvention can be performed by applying the above surface-treating agenton the surface of the base material such that the surface-treating agentcoats the surface. The method of coating is not specifically limited.For example, a wet coating method or a dry coating method can be used.

Examples of the wet coating method include dip coating, spin coating,flow coating, spray coating, roll coating, gravure coating, and asimilar method.

Examples of the dry coating method include deposition (usually, vacuumdeposition), sputtering, chemical vaper deposition (CVD) and a similarmethod. The specific examples of the deposition method (usually, vacuumdeposition) include resistance heating, electron beam, high-frequencyheating, ion beam, and a similar method. The specific examples of theCVD method include plasma-CVD, optical CVD, thermal CVD and a similarmethod. The deposition method is will be described below in more detail.

Additionally, coating can be performed by an atmospheric pressure plasmamethod.

The formation of the film is preferably performed so that thesurface-treating agent of the present invention is present together witha catalyst for hydrolysis and dehydration-condensation in the coating.Simply, when the wet coating method is used, after the surface-treatingagent of the present invention is diluted with a solvent, and just priorto applying it to the surface of the base material, the catalyst may beadded to the diluted solution of the surface-treating agent of thepresent invention. When the dry coating method is used, thesurface-treating agent of the present invention to which a catalyst hasbeen added is used itself in deposition (usually, vacuum deposition), orpellets may be used in the deposition (usually, the vacuum deposition),wherein the pellets is obtained by impregnating a porous metal such asiron or copper with the surface-treating agent of the present inventionto which the catalyst has been added.

As the catalyst which coexists with the surface-treating agent, anysuitable acid or base can be used. As the acid catalyst, for example,acetic acid, formic acid, trifluoroacetic acid, or the like can be used.As the base catalyst, for example, ammonia, an organic amine, or thelike can be used.

Next, the film is post-treated as necessary. This post-treatment is, butnot limited to, a treatment in which water supplying and dry heating aresequentially performed, in more particular, may be performed as follows.

After the film of the surface-treating agent of the present invention isformed on the surface of the base material as mentioned above, water issupplied to this film (hereinafter, referred to as precursor coating).The method of supplying water may be, for example, a method using dewcondensation due to the temperature difference between the precursorcoating (and the base material) and ambient atmosphere or spraying ofwater vapor (steam), but not specifically limited thereto.

It is considered that, when water is supplied to the precursor coating,water acts on a hydrolyzable group bonding to Si present in theperfluoro(poly)ether group containing silane compound in thesurface-treating agent of the present invention, thereby enabling rapidhydrolysis of the compound.

The supplying of water may be performed under an atmosphere, forexample, at a temperature of zero to 500° C., preferably 100° C. or moreand 300° C. or less. By supplying water at such temperature range,hydrolysis can proceed. The pressure at this time is not specificallylimited but simply may be ambient pressure.

Then, the precursor coating is heated on the surface of the basematerial under a dry atmosphere over 60° C. The method of dry heatingmay be to place the precursor coating together with the base material inan atmosphere at a temperature over 60° C., preferably over 100° C., andfor example, of 500° C. or less, preferably of 300° C. or less, and atunsaturated water vapor pressure, but not specifically limited thereto.The pressure at this time is not specifically limited but simply may beambient pressure.

Under such atmosphere, between the perfluoro(poly)ether group containingsilane compound of the present inventions, the groups (being hydroxylgroups when all R¹ are hydroxyl groups in the above mentioned compoundof any of the formula (1); hereinafter the same shall apply) bonding toSi after hydrolysis are rapidly dehydration-condensed with each other.Furthermore, between the compound and the base material, the groupbonding to Si in the compound after hydrolysis and a reactive grouppresent on the surface of the base material are rapidly reacted, andwhen the reactive group present on the surface of the base material is ahydroxyl group, dehydration-condensation is caused. As the result, thebond between the PFPE containing silane compounds of the presentinvention is formed, and the bond between the compound and the basematerial is formed. It is noted that if present, the fluorine-containingoil and/or the silicone oil is held or acquired by an affinity to theperfluoropolyether group containing silane compound.

The above supplying of water and dry heating may be sequentiallyperformed by using a superheated water vapor.

The superheated water vapor is a gas which is obtained by heating asaturated water vapor to a temperature over the boiling point, whereinthe gas, under an ambient pressure, has become to have a unsaturatedwater vapor pressure by heating to a temperature over 100° C., generallyof 500° C. or less, for example, of 300° C. or less, and over theboiling point. When the base material on which the precursor coating isformed is exposed to a superheated water vapor, firstly, due to thetemperature difference between the superheated water vapor and theprecursor coating of a relatively low temperature, dew condensation isgenerated on the surface of the precursor coating, thereby supplyingwater to the precursor coating. Presently, as the temperature differencebetween the superheated water vapor and the precursor coating decreases,water on the surface of the precursor coating is evaporated under thedry atmosphere of the superheated water vapor, and an amount of water onthe surface of the precursor coating gradually decreases. During theamount of water on the surface of the precursor coating is decreasing,that is, during the precursor coating is under the dry atmosphere, theprecursor coating on the surface of the base material contacts with thesuperheated water vapor, as a result, the precursor coating is heated tothe temperature of the superheated water vapor (temperature over 100° C.under ambient pressure). Therefore, by using a superheated water vapor,supplying of water and dry heating are enabled to be sequentiallycarried out simply by exposing the base material on which the precursorcoating is formed to a superheated water vapor.

As mentioned above, the post-treatment can be performed. It is notedthat though the post-treatment may be performed in order to furtherincrease friction durability, it is not essential in the producing ofthe article of the present invention. For example, after applying thesurface-treating agent to the surface of the base material, it may beenough to only stand the base material.

As described above, the surface-treating layer derived from the film ofthe surface-treating agent of the present invention is formed on thesurface of the base material to produce the article of the presentinvention. The surface-treating layer thus formed has high surface slipproperty and high friction durability. Furthermore, thissurface-treating layer may have water-repellency, oil-repellency,antifouling property (for example, preventing from adhering a foulingsuch as fingerprints), waterproof property (preventing infiltration ofwater into electrical components, and the like), surface slip property(or lubricity, for example, wiping property of a fouling such asfingerprints and excellent tactile feeling in a finger) depending on acomposition of the surface-treating agent used, in addition to highfriction durability, thus may be suitably used as a functional thinfilm.

The article having the surface-treating layer obtained according to thepresent invention is not specifically limited to, but may be an opticalmember. Examples of the optical member include the followings: displayssuch as a cathode ray tube (CRT; for example, TV, personal computermonitor), a liquid crystal display, a plasma display, an organic ELdisplay, an inorganic thin-film EL dot matrix display, a rear projectiondisplay, a vacuum fluorescent display (VFD), a field emission display(FED; Field Emission Display), or a front surface protective plate, anantireflection plate, a polarizing plate, or an anti-glare plate ofthese display, or these whose surface is subjected to antireflectiontreatment; lens of glasses, or the like; a touch panel sheet of aninstrument such as a mobile phone or a personal digital assistance; adisk surface of an optical disk such as a Blu-ray disk, a DVD disk, aCD-R or MO; an optical fiber, and the like; a display surface of aclock.

Other article having the surface-treating layer obtained according tothe present invention may be also a ceramic product, a pained surface, acloth product, a leather product, a medical product and a plaster.

Other article having the surface-treating layer obtained according tothe present invention may be also a medical equipment or a medicalmaterial.

The thickness of the surface-treating layer is not specifically limited.For the optical member, the thickness of the surface-treating layer iswithin the range of 1-30 nm, preferably 1-15 nm, in view of opticalperformance, friction durability and antifouling property.

Hereinbefore, the article produced by using the surface-treating agentof the present invention is described in detail. It is noted that anapplication, a method for using or a method for producing the articleare not limited to the above exemplification.

EXAMPLES

The perfluoro(poly)ether group containing silane compound, the processfor producing it and the surface-treating agent comprising it of thepresent invention will be described in detail through Examples, althoughthe present invention is not limited to Examples. It is noted that inExamples, the occurrence order of the four repeating units (CF₂O),(CF₂CF₂O), (CF₂CF₂CF₂O) and (CF₂CF₂CF₂CF₂O) constituting theperfluoropolyether of is not limited. The formula representing thecompound having a perfluoropolyether group shows an average composition.

Synthesizing Example 1: Preparation of a Perfluoropolyether CompoundHaving an Iodine at the Terminal

To a four necked flask of 1 L provided with a reflux condenser, athermometer and a stirrer, CF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂COOH (anaverage of b=24; 180 g) and hexafluorotetrachlorobutane (100 mL) wereadded, and an aqueous solution of potassium hydroxide (80 mL: containing4.87 g of potassium hydroxide) was added with stirring. The resultingsolution was dried. Hexafluorotetrachlorobutane (600 mL) and iodine werefurther added under a nitrogen stream in this order. This mixture washeated to 200° C., and maintained to progress iodination. The inorganicsalt was removed from the oil and hexafluorotetrachlorobutane wasdistilled off to obtain clear CF₃CF₂CF₂O(CF₂CF₂CF₂O)_(m)CF₂CF₂I (averageof m=24; 160 g).

Example 1: Preparation of a Perfluoropolyether Group Containing SilaneCompound Having an Iodine at the Terminal

To a four necked flask of 500 mL provided with a reflux condenser, athermometer and a stirrer, the perfluoropolyether compound having aniodine at the terminal obtained in Synthesizing Example 1 (90 g),3,5-bis(trifluoromethyl)benzonitrile (90 g) and vinyl trichlorosilane(10 g) were added in this order, and then di-tert-butylperoxide (2 g)was added. The mixture was heated to 145° C., and stirred at thistemperature for 7 hours. Then, a volatile content was distilled off toobtain a perfluoropolyether group containing silane compound havingiodine at the terminal (A) of the following

Example 2: Preparation of a Perfluoropolyether Group ContainingMethoxysilane Compound

To a four necked flask of 200 mL provided with a reflux condenser, athermometer and a stirrer, the perfluoropolyether group containingsilane compound having an iodine at the terminal (A) obtained in Example1 (20 g), m-xylene hexafluoride (40 g), and zinc powder (2.3 g) wereadded in this order, and then methanol (5 mL) was added under a nitrogenstream at a room temperature and reacted for 3 hours. To the reactionmixture, perfluorohexane (20 g) was added, and then the mixture waswashed with methanol. Then, a volatile content was distilled off under areduced pressure to obtain a perfluoropolyether group containingmethoxysilane compound having hydrogen at the terminal (B) (16 g). Thenumber average molecular weight of the compound was measured by ¹⁹F-NMR,as a result, it was 3,920.

Example 3

CF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂I (the average of b=35) was obtainedsimilarly to Synthesizing Example except for usingCF₃CF₂CF₂O(CF₂CF₂C₂O)_(b)CF₂CF₂COOH (the average of b=35) instead ofCF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂COOH (the average of b=24). Then, thecompound of the above formula (B) wherein b was 35 was obtainedsimilarly to Examples 1 and 2 except for using this compound. The numberaverage molecular weight of the compound was measured by ¹⁹F-NMR, as aresult, it was 5,690.

Example 4: Preparation of a Perfluoropolyether Group ContainingMethoxysilane Compound Having a Hydrogen at the Terminal

A compound having the iodine at the terminal (91 g) was obtainedsimilarly to Example 1 except that vinyl trimethoxysilane (9 g) was usedinstead of vinyl trichlorosilane. Then, to a four necked flask of 200 mLprovided with a reflux condenser, a thermometer and a stirrer, thecompound having an iodine at the terminal (20 g), perfluorohexane (20g), tert-butylalcohol (20 g) and a zinc powder (1.0 g) were added inthis order, and stirred at 45° C. for 7 hours. Then, the mixture waswashed with tetrahydrofuran. Then, a volatile content was distilled offunder a reduced pressure to obtain a perfluoropolyether group containingmethoxy silane compound having hydrogen at the terminal (B) (17 g).

Example 6: Preparation of a Perfluoropolyether Group ContainingMethoxysilane Compound Having an Iodine at the Terminal

To a four necked flask of 500 mL provided with a reflux condenser, athermometer and a stirrer, a perfluoropolyether compound having aniodine at the terminal (90 g) of an average composition: CF₃(OCF₂CF₂)₂₀(OCF₂)₁₆OCF₂CH₂OCF₂CHFOCF₂CF₂I (proviso with, the mixturecontains a slight amount of compounds comprising a slight amount ofrepeating units of (CF₂CF₂CF₂CF₂CF₂O) and/or (CF₂CF₂CF₂O)),3,5-bis(trifluoromethyl)benzonitrile (85 g), vinyl trichlorosilane (15g), and di-tert-butyl peroxide (2.7 g) were added in this order, andheated to 145° C. and stirred for 7 hours. Then, a volatile content wasdistilled off to obtain a perfluoropolyether group containing silanecompound having iodine at the terminal of the following formula (E) (82g).

Example 6: Preparation of a Perfluoropolyether Group ContainingMethoxysilane Compound Having a Hydrogen at the Terminal

To a four necked flask of 200 mL provided with a reflux condenser, theperfluoropolyether group containing silane compound having an iodine atthe terminal (E) (18 g) obtained in Example 5, m-xylene hexafluoride (30g), and zinc powder (1.5 g) were added in this order, and methanol (8mL) was added at a room temperature, and then heated to 45° C. andstirred for 7 hours. To the reaction mixture, perfluorohexane (20 g) wasadded, and the mixture was washed with methanol. Then, a volatilecontent was distilled off under a reduced pressure to obtain aperfluoropolyether group containing methoxysilane compound having ahydrogen at the terminal (F) (14 g). The number average molecular weightof the compound was measured by ¹⁹F-NMR, as a result, it was 4,000.

Comparative Example 1

Hexafluorotetrachlorobutane at the same amount was used instead of3,5-bis(trifluoromethyl)benzonitrile, heated to 120° C. and stirred atthis temperature overnight to obtain compound (A′) of the formula (A)similarly to Example 1. Then, the procedure of Example 2 was performedto obtain compound (B′) of the formula (B) (15 g). The number averagemolecular weight of the compound was measured by ¹⁹F-NMR, as a result,it was 4,000.

Comparative Example 2

CF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂I (the average of b=43) was obtainedsimilarly to Synthesizing Example except for usingCF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂COOH (the average of b=43) instead ofCF₃CF₂CF₂O(CF₂CF₂CF₂O)_(b)CF₂CF₂COOH (the average of b=24). Thiscompound was used and heated to 120° C. and stirred at this temperatureovernight to obtain compound (A′) of the formula (A) similarly toExample 1. Then, the procedure of Example 2 was performed to obtaincompound (B′) of the formula (B) wherein b is 43 (15 g).

The number average molecular weight of the compound was measured by¹⁹F-NMR, as a result, it was 4,000.

Evaluation Examples 7, 8, and 9 and Comparative Example 3

With respect to compounds (B) obtained in Example 2 and Example 4,compound (F) obtained in Example 6, and compound (B′) obtained inComparative Example 1, the number of the respective perfluoropolyether(PFPE) unit (a, b, c, d) and the number of the silane unit (g) weremeasured (Examples 7, 8, and 9 and Comparative Example 3, respectively).

Measurement Method

With respect to compounds (B) obtained in Example 2 and Example 4,compound (F) obtained in Example 6, and compound (B′) obtained inComparative Example 1, solution (A) wherein each compound (5 mg) wasdiluted in 2 mL of perfluorobutyl ethyl ether (HFE-7200, manufactured bySumitomo 3M Limited) and solution (B) wherein 2 mg of sodiumtrifluoroacetate was diluted in 1 mL of tetrahydrofuran were mixed atthe ratio of 20:1 (volume ratio A:B). 0.5 μL of this solution wasmeasured by using Matrix-assisted laser desorption time-of-flight massspectrometry (MALDI-TOF-MS) JMS S-3000 “Spiral TOF” manufactured by JEOLLtd. For calibration of the mass (m/z), polypropylene glycol having1,000 of an average molecular weight was used as external standard.

The results are shown the following Table 1. It is noted that theintensity of the compound wherein g is 7 or more is below themeasurement limit.

TABLE 1 Number of PFPE Intensity ratio (%) for each of the Numberaverage Weight average Compound units (average) number of silane units(g) of the number of the number Weight average/ used a b c d 1 2 3 4 5 6of silane units of silane units Number average Example 7 Example 2 0 180 0 7.1 10.7 37.4 30.8 9.6 4.3 3.4 3.7 1.1 Example 8 Example 3 0 35 0 017.6 27.9 19.4 14.6 11.3 9.2 3.0 3.8 1.3 Example 9 Example 6 1 1 20 164.1 17.1 52.1 17.2 8.2 1.3 3.2 3.4 1.1 Comparative Comparative 0 18 0 031.1 29.9 13.9 10.2 6.8 8.1 2.6 3.5 1.4 Example 3 Example 1

Intensity ratio (%) for each of the number of silane unit (g) when thesum of intensity for g is 1 to 6 was defined as 100% was calculated.Number average of the number of silane units (number average of g): Σ(g_(i) N _(i))/ΣN _(i)Weight average of the number of silane units (weight average of g): Σ(g_(i) ² N _(i))/Σ(g _(i) N _(i))wherein i is an integer of 1 or more, g_(i) means the value of g whenthe number of the repeating unit of the silane containing group is i,and N_(i) means the number of the compound wherein the number of therepeating units of the silane-containing group is i.

Weight average/Number average (polydispersity of g): Weight average ofthe number of silane units/Number average of the number of silane units

Preparation of a Surface-Treating Agent and Formation of aSurface-Treating Layer

Example 10

The compound obtained in Example 2 was dissolved in hydrofluoroether(Novec HFE7200 manufactured by Sumitomo 3M Ltd.)) such that theconcentration was 20 wt % to prepare Surface-treating agent 1.

Surface-treating agent 1 prepared in the above was vacuum deposited on aglass slide. Processing condition of the vacuum deposition was apressure of 3.0×10⁻³ Pa. The surface-treating agent of 2 mg wasvacuum-deposited per one plate of the glass slide (55 mm×100 mm). Then,the glass slide having the deposited layer was stood at 20° C. under anambient of humidity of 65% for 24 hours. Thereby, the deposited layerwas cured and the surface-treating layer was formed.

Examples 11 and 12

The surface-treating layers were formed similarly to Example 10 exceptthat the compound obtained in Example 3 and the compound obtained inExample 6 were used in place of the compound obtained in Example 2,respectively.

Comparative Example 4

The surface-treating agent was prepared and the surface-treating layerwas formed similarly to Example 10 except that the compound obtained inComparative Example 1 was used in place of the compound obtained inExample 2.

Evaluation of Surface Treating Layer (Evaluation of Friction Durability)

A static water contact angle of the surface-treating layers formed onthe surface of the base material in the above Examples 10-12 andComparative Example 4 respectively was measured. The static watercontact angle was measured for 1 μL of water by using a contact anglemeasuring instrument (manufactured by KYOWA INTERFACE SCIENCE Co.,Ltd.).

As an evaluation of the friction durability, a steel wool frictiondurability evaluation was performed. Specifically, the base material onwhich the surface-treating layer was formed was horizontally arranged,and then, a steel wool (grade No. 0000) was contacted with the exposedsurface of the surface-treating layer and a load of 1000 gf was appliedthereon. Then, the steel wool was shuttled at a rate of 140 mm/secondwhile applying the load.

The static water contact angle (degree) was measured per 1,000shuttling. The evaluation was stopped when the measured value of thecontact angle became to be less than 100 degree. The results are shownin Table 2.

TABLE 2 Number of Contact Angle (degree) rubbing Comparative (times)Example 10 Example 11 Example 12 Example 4 0 115.5 114.3 115.9 114.01000 111.9 113.7 113.8 110.5 2000 110.9 113.2 113.7 109.2 3000 109.5111.6 113.0 106.4 4000 108.4 111.0 112.7 98.8 5000 105.3 110.5 112.4 —6000 96.5 109.8 111.8 — 7000 — 109.4 111.5 — 8000 — 109.2 110.9 — 9000 —108.9 110.2 — 10000 — 108.2 109.2 — 11000 — 107.8 108.1 — 12000 — 105.3107.8 — 13000 — 104.6 105.0 — 14000 — 103.5 102.4 — 15000 — 103.0 102.0— 16000 — 98.4 97.2 —

As understood from Table 2, it was confirmed that Examples 10-12 usingthe surface-treating agent containing the perfluoropolyether groupcontaining silane compound of the present invention showed remarkablyincreased friction durability in comparison with Comparative Example 4wherein the compound wherein g is 2 or more is less than 80 mol %. Inaddition, it was confirmed that in the preparation of theperfluoropolyether group containing silane compound of the presentinvention, the addition reaction of vinyl silane could be progressed fora short time (7 hours).

INDUSTRIAL APPLICABILITY

The present invention is suitably applied for forming a surface-treatinglayer on a surface of various base materials, in particular, an opticalmember in which transparency is required.

The invention claimed is:
 1. A surface-treating agent comprising atleast one perfluoro(poly)ether group containing silane compound of theformula (1):

wherein: Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms; PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein, a, b, c and dare each independently an integer of 0 to 90, the sum of a, b, c and dis 1 or more, and the occurrence order of the respective repeating unitsin parentheses with the subscript a, b, c or d is not limited in theformula; Q is an oxygen atom or a divalent organic group; R¹ is ahydrogen atom or an alkyl group having 1 to 22 carbon atoms; R² is eachindependently a hydrogen atom or an inert monovalent organic group; X isa hydroxyl group or OR⁴; R⁴ is each independently at each occurrence asubstituted or unsubstituted C₁₋₁₂ alkyl group; Y is a hydrogen atom ora halogen atom; Z is a fluorine atom or a fluoroalkyl group having 1 to5 carbon atoms; e is an integer from 0 to 3; f is 0 or 1; g is aninteger from 1 to 10; h is an integer from 0 to 3; and n is an integerfrom 1 to 3, wherein a number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 6000 or less, polydispersity of g is more than 1.0 and less than2.0, and 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more.
 2. The surface-treating agent according to claim1 wherein the number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 5000 or less.
 3. The surface-treating agent according to claim 1wherein 90 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more.
 4. The surface-treating agent according to claim1 wherein 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is the compoundwherein g is 3 or more.
 5. The surface-treating agent according to claim1 wherein Rf is a perfluoroalkyl group having 1 to 10 carbon atoms. 6.The surface-treating agent according to claim 1 wherein PFPE is a group:—(OCF₂CF₂CF₂)_(b)— wherein b is an integer of 1 or more and 40 or less.7. The surface-treating agent according to claim 1 wherein PFPE is agroup—(OCF₂CF₂CF₂CF₂)_(a)—(OCF₂CF₂CF₂)_(b)—(OCF₂CF₂)_(c)—(OCF₂)_(d)— whereina and b is each independently an integer of 0 to 30, c and d is eachindependently an integer of 1 to 90, and the occurrence order of therespective repeating units in parentheses with the subscript a, b, c ord is not limited in the formula.
 8. The surface-treating agent accordingto claim 1, further comprising a solvent.
 9. The surface-treating agentaccording to claim 1, further comprising one or more other componentsselected from the group consisting of a fluorine-containing oil, asilicone oil and a catalyst.
 10. The surface-treating agent according toclaim 9 wherein the fluorine-containing oil is one or more compounds ofthe formula (2):Rf¹—(OC₄F₈)_(n′)—(OC₃F₆)_(b′)—(OC₂F₄)_(c′)—(OCF₂)_(d′)—Rf²  (2) wherein:Rf¹ is an alkyl group having 1 to 16 carbon atoms which may besubstituted by one or more fluorine atoms; Rf² is an alkyl group having1 to 16 carbon atoms which may be substituted by one or more fluorineatoms, a fluorine atom or a hydrogen atom; and a′, b′, c′ and d′ areeach independently an integer of 0 to 300, the sum of a′, b′, c′ and d′is at least one, and the occurrence order of the respective repeatingunits in parentheses with the subscript a′, b′, c′ or d′ is not limitedin the formula.
 11. The surface-treating agent according to claim 9wherein the fluorine-containing oil is one or more compounds of theformula (2a) or (2b):Rf¹—(OCF₂CF₂CF₂)_(b′)—Rf²  (2a)Rf¹—(OCF₂CF₂CF₂CF₂)_(a′)—(OCF₂CF₂CF₂)_(b′)—(OCF₂CF₂)_(c′)—(OCF₂)_(d′)—Rf²  (2b)wherein: Rf¹ is an alkyl group having 1 to 16 carbon atoms which may besubstituted by one or more fluorine atoms; Rf² is an alkyl group having1 to 16 carbon atoms which may be substituted by one or more fluorineatoms, a fluorine atom or a hydrogen atom; in the formula (2a), b′ is aninteger of 1 or more and 300 or less; in the formula (2b), a′ and b′ iseach independently an integer of 0 to 30, c′ and d′ is eachindependently an integer of 1 to 300, and the occurrence order of therespective repeating units in parentheses with the subscript a′, b′, c′or d′ is not limited in the formula.
 12. The surface-treating agentaccording to claim 1 which is used as an antifouling-coating agent or awaterproof-coating agent.
 13. A pellet comprising the surface-treatingagent according to claim
 1. 14. An article comprising a base materialand a layer which is formed on a surface of the base material from thesurface-treating agent according to claim
 1. 15. The article accordingto claim 14 wherein the base material is a glass.
 16. The articleaccording to claim 14 wherein the article is an optical member.
 17. Thearticle according to claim 14 wherein the article is a display.
 18. Aprocess for preparing a surface-treating agent comprising aperfluoro(poly)ether group containing silane compound of the formula(1):

wherein: Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms; PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a, b, c and dare each independently an integer of 0 to 90, the sum of a, b, c and dis at least 1, and the occurrence order of the respective repeatingunits in parentheses with the subscript a, b, c or d is not limited inthe formula; Q is an oxygen atom or a divalent organic group; R¹ is ahydrogen atom or an alkyl group having 1 to 22 carbon atoms; R² is eachindependently a hydrogen atom or an inert monovalent organic group; X isa hydroxyl group or OR⁴; R⁴ is each independently at each occurrence asubstituted or unsubstituted C₁₋₁₂ alkyl group; Y is a hydrogen atom ora halogen atom; Z is a fluorine atom or a fluoroalkyl group having 1 to5 carbon atoms; e is an integer from 0 to 3; f is 0 or 1; g is aninteger from 1 to 10; h is an integer from 0 to 3; and n is an integerfrom 1 to 3, wherein a number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 6000 or less, polydispersity of g is more than 1.0 and less than2.0, and 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more, comprising the steps of: reacting aperfluoro(poly)ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined for the formula (1) andY¹ is a chlorine, an iodine or a bromine, with a reactive double bondcontaining silane compound of the formula (1b):

wherein R¹, R², h and n are as defined for the formula (1), and X¹ is ahydroxyl group, a hydrolyzable group or a halogen atom in a fluorinecontaining aromatic compound, and then, optionally following steps (a)and/or (b): (a) when Y and Y¹ are different, converting Y¹ to Y; and (b)when X and X¹ are different, converting X¹ to X.
 19. A process forpreparing a surface-treating agent comprising a perfluoro(poly)ethergroup containing silane compound of the formula (1′):

wherein: Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms; PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein, a, b, c and dare each independently an integer of 0 to 90, the sum of a, b, c and dis at least 1, and the occurrence order of the respective repeatingunits in parentheses with the subscript a, b, c or d is not limited inthe formula; Q is an oxygen atom or a divalent organic group; R¹ is ahydrogen atom or an alkyl group having 1 to 22 carbon atoms; X is ahydroxyl group or OR⁴; R⁴ is each independently at each occurrence asubstituted or unsubstituted C₁₋₁₂ alkyl group; Z is a fluorine atom ora fluoroalkyl group having 1 to 5 carbon atoms; e is an integer from 0to 3; f is 0 or 1; g is an integer from 1 to 10; and his an integer from0 to 3; wherein a number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 6000 or less, polydispersity of g is more than 1.0 and less than2.0, and 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more, comprising the steps of: reacting aperfluoro(poly)ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined above, and Y¹ is achlorine, an iodine or a bromine, with a compound of the formula (1c):

wherein R¹ and h are as defined above, in a fluorine containing aromaticcompound to obtain a compound of the formula (1d):

wherein Rf, PFPE, Q, Y¹, Z, R¹, e, f, g and h are as defined above, andthen reacting the obtained compound with a compound of HX wherein X isas defined above.
 20. The process according to claim 18 wherein thefluorine containing aromatic compound is selected from the groupconsisting of perfluorobenzene, pentafluorobenzene,1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene,1,2,4,5-tetrafluorobenzene, 1,2,3-trifluorobenzene,1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene, benzotrifluoride,fluorobenzene, 1-chloro-2-fluorobenzene, 1-chloro-3-fluorobenzene,1-chloro-4-fluorobenzene, 2,6-dichlorofluorobenzene,1-fluoro-3-(trifluoromethoxy)benzene, 1-fluoro-2,4-dinitrobenzene,2,4-dimethoxy-1-fluorobenzene, 1-fluoro-4-nitrobenzene, 2-fluorotoluene,3-fluorotoluene, 4-fluorotoluene, 3-fluorobenzotrifluoride,1-chloro-2,4-difluorobenzene, 1-chloro-3,4-difluorobenzene,1-chloro-3,5-difluorobenzene, 2-chloro-1,3-difluorobenzene,chloropentafluorobenzene, 2,4-dichlorofluorobenzene,2,5-dichlorofluorobenzene, 2,6-dichlorofluorobenzene,1,2-dichloro-4-fluorobenzene, 1,3-dichloro-5-fluorobenzene,1,3-dichloro-2,4,6-trifluorobenzene, 3,4-difluorobenzonitrile,3,5-difluorobenzonitrile, 3,4-difluoronitrobenzene,1-ethoxy-2,3-difluorobenzene, 1,2-dicyano-4,5-difluorobenzene,1-acetoxy-3-fluorobenzene, 1-acetoxy-4-fluorobenzene,1-acetonyl-4-fluorobenzene, 2-fluoro-m-xylene, 3-fluoro-o-xylene,4-fluoro-o-xylene, pentafluoroanisole, tetrafluorophthalonitrile,2-trifluoromethylbenzal chloride, 3-trifluoromethylbenzal chloride,4-trifluoromethylbenzal chloride, methyl 3-(trifluoromethyl)benzoate,difluorobenzonitrile, bistrifluoromethyl benzonitrile, 4-trifluoromethylbenzonitrile, aminobenzotrifluoride, and trifluoromethylaniline.
 21. Theprocess according to claim 18 wherein the fluorine containing aromaticcompound is a fluorine containing aromatic compound having 0 to 3 debyesof polarizability.
 22. The process according to claim 18 wherein thefluorine containing aromatic compound is selected from the groupconsisting of benzotrifluoride, difluorobenzonitrile, andbistrifluoromethyl benzonitrile.
 23. A surface-treating agent comprisingat least one perfluoro(poly)ether group containing silane compound ofthe formula (1):

wherein: Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms; PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a, b, c and dare each independently an integer of 0 to 90, the sum of a, b, c and dis at least 1, and the occurrence order of the respective repeatingunits in parentheses with the subscript a, b, c or d is not limited inthe formula; Q is an oxygen atom or a divalent organic group; R¹ is ahydrogen atom or an alkyl group having 1 to 22 carbon atoms; R² is eachindependently a hydrogen atom or an inert monovalent organic group; X isa hydroxyl group or OR⁴; R⁴ is each independently at each occurrence asubstituted or unsubstituted C₁₋₁₂ alkyl group; Y is a hydrogen atom ora halogen atom; Z is a fluorine atom or a fluoroalkyl group having 1 to5 carbon atoms; e is an integer from 0 to 3; f is 0 or 1; g is aninteger from 1 to 10; h is an integer from 0 to 3; and n is an integerfrom 1 to 3, wherein a number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 6000 or less, polydispersity of g is more than 1.0 and less than2.0, and 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more, wherein the perfluoro(poly)ether groupcontaining silane compound of the formula (1) is prepared by reacting aperfluoro(poly)ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined for the formula (1) andY¹ is a chlorine, an iodine or a bromine, with a reactive double bondcontaining silane compound of the formula (1b):

wherein R¹, R², h and n are as defined for the formula (1), and X¹ is ahydroxyl group, a hydrolyzable group or a halogen atom in a fluorinecontaining aromatic compound, and then, optionally following steps (a)and/or (b): (a) when Y and Y¹ are different, converting Y¹ to Y; and (b)when X and X¹ are different, converting X¹ to X.
 24. A surface-treatingagent comprising at least one perfluoro(poly)ether group containingsilane compound of the formula (1′):

wherein: Rf is an alkyl group having 1 to 10 carbon atoms which may besubstituted by one or more fluorine atoms; PFPE is—(OC₄F₈)_(a)—(OC₃F₆)_(b)—(OC₂F₄)_(c)—(OCF₂)_(d)— wherein a, b, c and dare each independently an integer of 0 to 90, the sum of a, b, c and dis at least 1, and the occurrence order of the respective repeatingunits in parentheses with the subscript a, b, c or d is not limited inthe formula; Q is an oxygen atom or a divalent organic group; R¹ is ahydrogen atom or an alkyl group having 1 to 22 carbon atoms; X is ahydroxyl group or OR⁴; R⁴ is each independently at each occurrence asubstituted or unsubstituted C₁₋₁₂ alkyl group; Z is a fluorine atom ora fluoroalkyl group having 1 to 5 carbon atoms; e is an integer from 0to 3; f is 0 or 1; g is an integer from 1 to 10; and his an integer from0 to 3; wherein a number average molecular weight of theperfluoro(poly)ether group containing silane compound is 3000 or moreand 6000 or less, polydispersity of g is more than 1.0 and less than2.0, and 80 mol % or more of the perfluoro(poly)ether group containingsilane compound contained in the surface-treating agent is a compoundwherein g is 2 or more, wherein the perfluoro(poly)ether groupcontaining silane compound of the formula (1′) is prepared by reacting aperfluoro(poly)ether compound of the formula (1a):

wherein Rf, PFPE, Q, Z, e and f are as defined above, and Y¹ is achlorine, an iodine or a bromine, with a compound of the formula (1c):

wherein R¹ and h are as defined above, in a fluorine containing aromaticcompound to obtain a compound of the formula (1d):

wherein Rf, PFPE, Q, Y¹, Z, R¹, e, f, g and h are as defined above, andthen reacting the obtained compound with a compound of HX wherein X isas defined above.
 25. The surface-treating agent according to claim 23wherein the fluorine containing aromatic compound is selected from thegroup consisting of perfluorobenzene, pentafluorobenzene,1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene,1,2,4,5-tetrafluorobenzene, 1,2,3-trifluorobenzene,1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene, benzotrifluoride,fluorobenzene, 1-chloro-2-fluorobenzene, 1-chloro-3-fluorobenzene,1-chloro-4-fluorobenzene, 2,6-dichlorofluorobenzene,1-fluoro-3-(trifluoromethoxy)benzene, 1-fluoro-2,4-dinitrobenzene,2,4-dimethoxy-1-fluorobenzene, 1-fluoro-4-nitrobenzene, 2-fluorotoluene,3-fluorotoluene, 4-fluorotoluene, 3-fluorobenzotrifluoride,1-chloro-2,4-difluorobenzene, 1-chloro-3,4-difluorobenzene,1-chloro-3,5-difluorobenzene, 2-chloro-1,3-difluorobenzene,chloropentafluorobenzene, 2,4-dichlorofluorobenzene,2,5-dichlorofluorobenzene, 2,6-dichlorofluorobenzene,1,2-dichloro-4-fluorobenzene, 1,3-dichloro-5-fluorobenzene,1,3-dichloro-2,4,6-trifluorobenzene, 3,4-difluorobenzonitrile,3,5-difluorobenzonitrile, 3,4-difluoronitrobenzene,1-ethoxy-2,3-difluorobenzene, 1,2-dicyano-4,5-difluorobenzene,1-acetoxy-3-fluorobenzene, 1-acetoxy-4-fluorobenzene,1-acetonyl-4-fluorobenzene, 2-fluoro-m-xylene, 3-fluoro-o-xylene,4-fluoro-o-xylene, pentafluoroanisole, tetrafluorophthalonitrile,2-trifluoromethylbenzal chloride, 3-trifluoromethylbenzal chloride,4-trifluoromethylbenzal chloride, methyl 3-(trifluoromethyl)benzoate,difluorobenzonitrile, bistrifluoromethyl benzonitrile, 4-trifluoromethylbenzonitrile, aminobenzotrifluoride, and trifluoromethyl aniline. 26.The surface-treating agent according to claim 23 wherein the fluorinecontaining aromatic compound is a fluorine containing aromatic compoundhaving 0 to 3 debyes of polarizability.
 27. The surface-treating agentaccording to claim 23 wherein the fluorine containing aromatic compoundis selected from the group consisting of benzotrifluoride,difluorobenzonitrile, and bistrifluoromethyl benzonitrile.
 28. Theprocess according to claim 19 wherein the fluorine containing aromaticcompound is selected from the group consisting of perfluorobenzene,pentafluorobenzene, 1,2,3,4-tetrafluorobenzene,1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene,1,2,3-trifluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene,benzotrifluoride, fluorobenzene, 1-chloro-2-fluorobenzene,1-chloro-3-fluorobenzene, 1-chloro-4-fluorobenzene,2,6-dichlorofluorobenzene, 1-fluoro-3-(trifluoromethoxy)benzene,1-fluoro-2,4-dinitrobenzene, 2,4-dimethoxy-1-fluorobenzene,1-fluoro-4-nitrobenzene, 2-fluorotoluene, 3-fluorotoluene,4-fluorotoluene, 3-fluorobenzotrifluoride, 1-chloro-2,4-difluorobenzene,1-chloro-3,4-difluorobenzene, 1-chloro-3,5-difluorobenzene,2-chloro-1,3-difluorobenzene, chloropentafluorobenzene,2,4-dichlorofluorobenzene, 2,5-dichlorofluorobenzene,2,6-dichlorofluorobenzene, 1,2-dichloro-4-fluorobenzene,1,3-dichloro-5-fluorobenzene, 1,3-dichloro-2,4,6-trifluorobenzene,3,4-difluorobenzonitrile, 3,5-difluorobenzonitrile,3,4-difluoronitrobenzene, 1-ethoxy-2,3-difluorobenzene,1,2-dicyano-4,5-difluorobenzene, 1-acetoxy-3-fluorobenzene,1-acetoxy-4-fluorobenzene, 1-acetonyl-4-fluorobenzene,2-fluoro-m-xylene, 3-fluoro-o-xylene, 4-fluoro-o-xylene,pentafluoroanisole, tetrafluorophthalonitrile, 2-trifluoromethylbenzalchloride, 3-trifluoromethylbenzal chloride, 4-trifluoromethylbenzalchloride, methyl 3-(trifluoromethyl)benzoate, difluorobenzonitrile,bistrifluoromethyl benzonitrile, 4-trifluoromethyl benzonitrile,aminobenzotrifluoride, and trifluoromethylaniline.
 29. The processaccording to claim 19 wherein the fluorine containing aromatic compoundis a fluorine containing aromatic compound having 0 to 3 debyes ofpolarizability.
 30. The process according to claim 19 wherein thefluorine containing aromatic compound is selected from the groupconsisting of benzotrifluoride, difluorobenzonitrile, andbistrifluoromethyl benzonitrile.
 31. The surface-treating agentaccording to claim 24 wherein the fluorine containing aromatic compoundis selected from the group consisting of perfluorobenzene,pentafluorobenzene, 1,2,3,4-tetrafluorobenzene,1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene,1,2,3-trifluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene,benzotrifluoride, fluorobenzene, 1-chloro-2-fluorobenzene,1-chloro-3-fluorobenzene, 1-chloro-4-fluorobenzene,2,6-dichlorofluorobenzene, 1-fluoro-3-(trifluoromethoxy)benzene,1-fluoro-2,4-dinitrobenzene, 2,4-dimethoxy-1-fluorobenzene,1-fluoro-4-nitrobenzene, 2-fluorotoluene, 3-fluorotoluene,4-fluorotoluene, 3-fluorobenzotrifluoride, 1-chloro-2,4-difluorobenzene,1-chloro-3,4-difluorobenzene, 1-chloro-3,5-difluorobenzene,2-chloro-1,3-difluorobenzene, chloropentafluorobenzene,2,4-dichlorofluorobenzene, 2,5-dichlorofluorobenzene,2,6-dichlorofluorobenzene, 1,2-dichloro-4-fluorobenzene,1,3-dichloro-5-fluorobenzene, 1,3-dichloro-2,4,6-trifluorobenzene,3,4-difluorobenzonitrile, 3,5-difluorobenzonitrile,3,4-difluoronitrobenzene, 1-ethoxy-2,3-difluorobenzene,1,2-dicyano-4,5-difluorobenzene, 1-acetoxy-3-fluorobenzene,1-acetoxy-4-fluorobenzene, 1-acetonyl-4-fluorobenzene,2-fluoro-m-xylene, 3-fluoro-o-xylene, 4-fluoro-o-xylene,pentafluoroanisole, tetrafluorophthalonitrile, 2-trifluoromethylbenzalchloride, 3-trifluoromethylbenzal chloride, 4-trifluoromethylbenzalchloride, methyl 3-(trifluoromethyl)benzoate, difluorobenzonitrile,bistrifluoromethyl benzonitrile, 4-trifluoromethyl benzonitrile,aminobenzotrifluoride, and trifluoromethylaniline.
 32. Thesurface-treating agent according to claim 24 wherein the fluorinecontaining aromatic compound is a fluorine containing aromatic compoundhaving 0 to 3 debyes of polarizability.
 33. The surface-treating agentaccording to claim 24 wherein the fluorine containing aromatic compoundis selected from the group consisting of benzotrifluoride,difluorobenzonitrile, and bistrifluoromethyl benzonitrile.